Detailed definition
Section 503A of the Federal Food, Drug, and Cosmetic Act (added by the FDA Modernization Act of 1997) governs traditional pharmacy compounding. 503A pharmacies prepare medications for specific identified patients pursuant to a valid prescription. They are exempt from FDA new-drug approval, current Good Manufacturing Practice (cGMP) requirements, and labeling requirements that apply to mass-produced drugs. They are regulated by state boards of pharmacy. 503A compounding is appropriate when an FDA-approved product is unavailable at the needed dose, vehicle, or combination, or when a patient has documented allergies to inactive ingredients in approved products.
Why it matters in menopause
Compounded HRT (Bi-est, custom estradiol and progesterone preparations) is typically 503A-compounded. The trade-off is flexibility in formulation vs. absence of batch-tested potency assurance. ClearedRx prescribes from 503A compounding pharmacies when there is a specific patient-level reason; otherwise FDA-approved products are the default.
Related terms
Sources
External references: Wikipedia.